Carburetor



Oct. 28, 1952 A. H. WINKLER 2,615,440

CARBURETOR Filed Dec. 30, 1947 4 Sheets-Sheet l I/VVENTOB flLB /er H.W/N/(LEB ATTOENE Y Oct. 28, 1952 H, wlNKLER 2,615,440

CARBURETOR Filed Dec. 30, 1947 4 Sheets-Sheet 2 SPARK ADVANCE IN VENTOR.

' 455E121- H. lA/INKLE'IZ A TTOENEY A. H. WINKLER CARBURETOR Oct. 28,1952 4 Sheets-Sheed 5 Filed Dec. 30, 1947 IN VEN TOR. 45am H. WINKLERATTORNEY Oct. 28, 1952 A. H. WINKLER 2,615,440

CARBURETOR Filed Dec. 50, 1947 4 Sheets-Sheet 4 IN VEN TOR.

AIEYBERT H. Wmxwz A TTOENEY Patented Oct. 28, 1952 was AlbertH..Wink'ler,.iS0uth Bend,'Ind., assignor to Bendix Aviation Corporation,SouthBend, ImL,

a corporation ofv Delaware Application December 30, 1 947,'Serial No.794,560 A The present invention'relates toa fuel supply system and moreparticularly to a carburetor for an internal combustion engineadapted tooperate under certain conditions on less than the full number ofcylinders. This type of engine I is illustrated in my'c'op'endin'g"application Serial No. 751,282 .filed' May 29, 1947; and willbereferred to hereinafter as a"splitengine. Some ofthe cylindersof'thesplit engine, for example three cylinders of a six cylinderengine, are in operation throughout "'the entire time the engine is inoperation, whilethe remaining cylinders may be in operationonly duringstartingi-power pickup "and high power :output. For convenience ofdescription, the runningfof the engine on the full number of cylinderswill be referred to as standard engine operation "and the "running ofthe engine on only a part ofthe cylinders as split engine operation.Thecylinders which are in continuous operation will be referred to asstandard cylinders andthose which are in operation only during starting,'powerpick-up and high power output-as power cylinders. In the splitengine disclosed in my copending"application, the power cylindersarerendered inopera-' tons'of the power cylinders, While continuing toreciprocate, do not expel theexhaust gases containedin their respectivecylinders, nor do said cylinders receive new charges of fuel 'air. Inthis arrangement; either a s-ingle intake manifold for all the cylindersof the engine or two separate manifolds, one forthestandard cylindersand the other for the-power cylinders, may be used.

;One Ofthe principal objects of thepresent invention is to provideacarburetor for a split engine which willsupply theproper fuel-air ratioto said engine throughout itsentire range of operation.

Anotherobjectof the inventionis to provide a carburetor forasplit enginewherein the supply or. fuel-air mixture is automatically adjusted forstandard or split engine operationas the engine shifts between saidoperations.

Another object of the inventionisto provide a device in combination withthe aforementioned carburetor for adjusting "a spark advancemechanism-to standard and split engine operations.

Additional objects and advantages will appear fromthe followingdescription and accompanying drawings wherein one embodiment of my-in-"vention is disclosed. The invention may be in 15-Claim s. (01. 123-127)combination'with either 'a single or a double barrel carburetor and isnot limited to any particular type of split engine, but is understood tobe generally applicable to any of said engines whereinthe control of thepower cylinders includes a'meansposterior to thefuel supply nozzle forinterrupting the flow of air through the present invention;

Figure 2 is aschematic view of the carburetor, showing the variouselements rearranged to moreclearly illustrate their operativerelationship to one another;

Figure 3 is asectional view" taken on line 22 ofFigure 2;

Figure 4'is atop plan view of the carburetor;

Figure 5 is a side'elevation of the carburetor;

Figure 6"is a detailed sectional view of the power enrichmentjet and thevalve control mechanism therefor;

Figure 7 is a detailed celerating pump; and

Figured is a detailed view'of the idle system, showing the inductionpasage of the carburetor in cross-section. a v y The present inventionmay be readilyxunderstood by referring to the accompanying drawingsin'which Figure 1 shows a multiple cylinder internal combustion'enginein combination with the present enginecontrol mechanism wherein numeral[designates acarburetor, 2 a sparked; vancermec'hanism, 3 a vacuumactuated switch for the split engine-control, t ;a manuallyactusectionalview of the acated switch'for'saidcontrol, 5a speed responsive switchfor said'control, 6 a temperature responsiveswitch, and! a tapptassembly for'controlling the operation of a portion of the cylinders,said tappet'assembly being actuated 'by-asolenoid mechanismB-in-responseto'the aforementioned control switches. The'severalswitches are connected by leads to relays in box-9 which turn controlsolenoid mechanism 8. -Withthe exception of the mechanism forrendering aportion 3 the induction passage of the carburetor, I2 the air inlet, I4the mixture outlet, I5 a choke valve, and IS a throttle valve, saidthrottle valve being mounted on a throttle valve shaft I 8 journaled inthe throttle body of 'the carburetor. The fuel is discharged into theinduction passage at the throat of venturi 26 through discharge nozzle22 which communicates with a fuel bowl 24 through fuel well 26, a mainfuel conduit 28 and the main fuel metering jet 30 disposed in one end ofsaid conduit adjacent the bottom of fuel bowl 24. The fuel well includesa sleeve 49 having several small holes 42 uniformly spaced over thesurface thereof and four large fuel orifices 44 near the bottom endthereof on a plane with conduit 2B. The sleeve 40 is spaced from theinternal wall of the well to permit air to surround the sleeve and passthrough holes 42 into the internal portion of said sleeve. Air isadmitted into well 26 from the air intake end I2 of the inductionpassage through port 56 and is metered at orifice 52 as it passesdownwardly through passage 54 into the annular space between sleeve 46and the side wall of the well. In this construction, the fuel flows frombowl 24 through metering orifice 3B, conduit 28 and holes 44 into sleeve48 and passes upwardly through said sleeve where it forms an emulsionwith the air admitted from the annular space about the sleeve throughholes 42. The fuel-air emulsion is then discharged through nozzle 22into the throat of the venturi 20. A conventional fuel inlet valve andfloat mechanism for controlling the operation of said valve are shown atnumerals 69 and 62, respectively.

The construction of the fuel discharge nozzle may be more fullyunderstood by referring to Figure 8 wherein another cross-sectional viewis shown. It is seen that nozzle 22 discharges the fuel adjacent theunder side of a, horizontal bar 48 formed integrally with venturi 26.The fuel discharge end of the nozzle is provided with a downwardlytapering ear 49 which prevents the fuel from flowing along the underside of said nozzle to the venturi and thence down the side wall of theinduction passage. A similar ear 5| is disposed on the opposite side ofthe venturi under bar 48. Novel features of the fuel discharge systemshown in Figures 2 and 8 are claimed in a divisional application SerialNo. 293,730, filed June 16, 1952 and in my oopending application SerialNo. 8,951, filed February 17, 1948.

To provide an increased quantity of fuel for standard engine operation,main fuel conduit 28 is connected with the fuel bowl by an auxiliarymetering jet 'IIJ disposed downstream from .iet 30. This auxiliary jetI0 is controlled by a valve I2 urged to its closed position for split enine operation by spring 14 and to its open position for standard engineoperation by a reciprocable rod I8 moved in the direction to open saidValve by a spring I8 reacting betweenplate 80 secured to the lower endof said rod and an external shoulder 82 on bushing 84. When rod 16 is inits lowermost position, valve 12 is held open so that the fuel will flowthrough jet I6 into the valve sleeve and thence through a plurality oforifices 86 into conduit 28. The means for actuating rod I6 will bedescribed more fully hereinafter.

A power enrichment jet 99 connects the fuel bowl with the main fuelconduit 28 posterior to the main jet 30 and auxiliary fuel jet T0 and scontrolled by a valve 92 urged to its closed position by a Spring 94.Valve92 is operated y a 4 reciprocable rod 96 which is urged in thedirection to open said valve by a spring 98 reacting between a plate I00secured to the lower end of said rod and a plate I02 near the upper endthereof. Rod 96 is secured to and actuated by a piston I84 mounted in acylinder I06 which is connected at its upper end by a conduit (notshown) with the induction passage on the engine side of throttle valveI6.

A manually actuated accelerating pump generally shown at III) consistsof a cylinder H2, a piston II and a lever II6 connecting the upperportion of said piston I I4 with the throttle valve actuating mechanismI I 8 mounted on the lefthand end o'f shaft I8, as shown in Figure 2.The upper end of lever H6 is disposed in a slot I 20, as shown in Figure7, and is yieldably urged toward the upper end of piston II4 by a springI22 reacting between the lower internal end of piston H4 and the underside of a lever support I24. thus providing a follow-up arrangement forpiston [I4 in discharging fuel from cylinder H2. When the piston H4 israised, fuel flows from the fuel bowl into the lower portion of cylinderI I2 through a valve controlled orifice I26, and as the piston is moveddownwardly on the-opening movement of the throttle valve, the fueldischarges from the lower end of cylinder II2 through conduit I28 anddischarge orifice I36 disposed near the throat of venturi 20. An airduct I32 connects the upper end of conduit I28 with the inductionpassage I0 above venturi 20 to break the efifect of Venturi vacuum onthe fuel in conduit I28. A ball I34 of a ball checkvalve is disposed inan enlarged portion I35 of conduit I28 and is adapted to seat over thefuel inlet of the enlarged-portion when the accelerating pump isinoperative and to seat over air inlet, i. e. the lower end of duct I32, when fuel is being discharged from the accelerating pump. The ballI34 thus permits air to bleed through the pump discharge orifice whenthe pump is not in operation and prevents the suction in the throat ofthe venturi' from drawing fuel from the pump cylinder. During theoperation of the pump, the

ball I34 seats over the lower end of duct I32 and prevents the fuel frombeing discharged by the accelerating pump through duct I32.

A conduit I40 connects the spark advance mechanism 2 with the inductionpassage on the engine side of the throttle Valve. A duct I42 is adaptedto bleed air into conduit I49 during split engine operation and thuslower the effect of manifold vacuum in the spark advance mechanism. Theduct I42 is controlled by a valve I44 mounted in valve sleeve I46 andurged to its closed position over orifice I41 by a spring I48. The'valveI44 is actuated by a reciprocable rod I50 mounted in a bushing I52 andurged in the direction to open said valve by a spring I54 reactingbetween a plate I56 secured to the lower end ofsaid rod and an externalshoulder on bushing I52.

The idle system of the carburetor, which is best shown in Figure 8,consists of two vertically arranged conduits I 60 and I62 which connectthe lower portion of well 26 adjacent holes 44 with idle discharge portsI64 and I66 above and below throttle valve I6, respectively. A bleed I88having an orifice I'IO is provided to admit air into the system forforming an emulsion with the fuel as it enters conduit I62. When thethrottle valve is in closed or nearly closed position, fuel flows fromwell 26 through conduits I66 and IE2 and after mixing with air admittedthrough the idle'alr bleed I68, discharges .through'rport I66.Additional air is bled into the idle air system at port I64whenthe edgeof throttle valve I6 is below said'port. As the throttle valve is openedand the edge thereof passes above port I64, fuel discharges throughboth'ports' I64 and IE6, thus providing additional fuel for theincreased flow of air. An idle adjustment valve I12 controls thequantity of fuel-air emulsion discharged through port I66.

During split engine operation; the power en- 'richment valve 92, theauxiliary valve I2 and air bleed valve I44 are held in the positionshown'in Figure 2, i. e. all three valves are held in closed position.The actuating rods 98, I6 and I50, for these valves respectively, arecontrolled by a solenoid I80 '(Figures 4 and 5)" through a lever I82anda rotatable shaft I84 having rmounted thereon levers I85, I86, I81and I88 for the power enrichment valve, auxiliary valve, spark advancevalve, and accelerating pump, respectively. When the solenoid isactuated, lever I82 moves'to the right,- as shown in Figure 5, rotatingshaft I84 a part turn in the clockwise direction, lifting levers I86 andI81 which in turn lift rods I6 and I50, thus permitting valves I2 andI44 to close In the clockwise movement of shaft I84 and lever I 85, stemI80 moves axially until the free end thereof projects into'cylinder I06under piston I04, as shown in Figure 6, and prevents rod 98 from openingvalve 82 of the power jetwhen the manifold vacuum becomes .too low toretain piston I04 .in' the upper end of cylinder I86. A yieldableconnection is provided on stem M9 to permit continued operation of thelevers on shaft I84 should stem I89 be prevented from moving by thepresence of piston H14 in the lower end of cylinder I06. A stem I94operated by lever I88 is similar in construction and operation to stem,i89 and is provided for the purpose of limiting the stroke of theaccelerating pump during split engine operation to less than that duringstandard operation.

During standard operation of the engine, solenoid I80 is de-energized,thus permitting spring I8 of the auxiliary fuel jet and spring I54 ofthe spark advance mechanism to open valveslZ and I44, respectively.Thus, fuel flows through main fuel metering jet 30, auxiliary fuel jetI0 and conduit 28, into well 28. Since the manifold vacuum is somewhatgreater for any given speedwhen all the cylinders are operating thanwhen only a part of the cylinders are operating, the effectof saidvacuum on the spark advance mechanism must be modified if the mechanismis to operate satisfactorily .during split engine operation. Thus, valveI44 is held open during standard engine operation to admit air intoconduit I48 and thus decrease the vacuum transmitted from the inductionpassage to .thespark advance mechanism. In standard operatiomv theaccelerating pump and power enrichment jet operate asin conventionalcarburetors, i. e. the accelerating pump piston moves through a fullstroke when the throttle valve'iismoved from closedto wide openposition, and the power. enrichment jet is opened whenever the manifoldvacuum falls below a predetermined value enabling spring eli to move rod86 in the direction to open power enrichment valve. 92.

When the engineshifts. from. standard to split engine operation, thesolenoid I88 is energized, moving lever I82to the'right, as shown inFigure 5, .and1rotatingshaft I84 a clockwise .direction, thus liftingrod I8. of the. auxiliary'jet and rod I50of ithessparkfadvance bleed to,per- In most split engine operations, it has been found that thepulsations of the engine running on a relatively small. number ofcylinders cause. the fuel-air mixture to become richer so that no'enrichment mechanism such as jet 88 is required for high power output.Thus; when solenoid I is-energized in the shift to split engineoperation,'stem I89-moves under piston I84 so that springs!!! cannotlower rod 86 and open the power enrichment valve 92 when the manifoldvacuum isdecreasedbelow a predeterrninedvalue. Also, when the solenoidis energized, stem I84 moves into the path of a shoulder on the upperportion of piston II4,'thus preventing the piston from completing itsfull stroke. The yieldable connection between. lever H8 and piston H4,

however, permitsthethrottle valve to move to v its wideopen position.

While only'oneembodiment of the invention has beendescribed herein,thereare certain conditions in which a rearrangement of the elementscomprising the carburetor :may be desirable, for.

example, when'the carburetor is used on an engine having a large numberof cylinders, the pulsations of thestandard cylinders in split en gine.operation may not be of sufiicient magnitude to'materiallyenrich thefuel; therefore, the operation of the, power enrichment Jet 08 for splitengine operation may under certain circumstances, be desirable Manyother changes may bemade'in the construction of the present carburetorto suit requirements.

. I claim:

l. Acarburetor for a:split engine comprising an induction passage; athrottle in said induction passage, a means formanually actuating saidthrottle, a main fuel discharge jet, a fuel bowl, a fuel conduitconnecting said discharge jet with said fuel bowl, a main fuel meteringorifice in said conduit and an auxiliary fuel metering orificeconnectin'grsaid fuel bowl with saidv conduit posteriorto saidmainmetering orifice, a valve for controllingsaid auxiliary orifice, apower enrichment orifice connecting said fuel bowl with mittingmanifoldvacuum to a spark advance mechanism, a duct for bleeding air into saidpassagewayrto lessen'the effect of said vacuum on said mechanism,a'valve for c'ontrolling said duct, and an electrically actuated meansso constructed and arrangedias' to open'said auxiliary and duct valvesfor standard engine operation and to close said valves, preventactuation of said vacuum controlled member of the power enrichment valveand limit the stroke. ofsaid accelerating pump for split-engineoperation.

-. 2. A carburetorfor' a split engine comprising an inductionpassage,.a-throttle in said induction passage, a main. fuel discharge.jet,: a fuel bowl,

:a-main fuelconduit connecting said discharge Jet with said fuel bowl, amain fuel metering orifice an-sald'conduiwan auxiliary fuelmeteringorifice connecting said fuel bowl with said conduit posterior to saidmain metering orifice, a valve for controlling said auxiliary orifice, apower enrichment orifice connecting said fuel bowl with said conduitposterior to said main metering orifice, a valve for controlling saidpower enrichment orifice, a vacuum controlled member for opening saidpower enrichment valve, an accelerating pump yieldably connected to ameans for actuating said throttle valve, a passageway for transmittingmanifold vacuum to a spark advance mechanism, a duct for bleeding airinto said passageway to lessen the effect of said vacuum on saidmechanism, a valve for controlling said duct, and a means so constructedand arranged as to open said auxiliary and duct valves for standardengine operation and to close said valves, prevent actuation of thevacuum'controlled member of the power enrichment valve, and limit thestroke of said accelerating pump for split engine operation.

3. A carburetor for a split engine comprising an induction passage, athrottle in said induction passage, an actuating means for saidthrottle, a main fuel discharge jet, a fuelbowl, a main fuel conduitconnecting said discharge jet with said fuel bowl, a main meteringorifice in said conduit, an auxiliary fuel metering orifice connectingsaid fuel bowl with said conduit posterior to said mainmetering orifice,a valve for controlling said auxiliary orifice, a power en'- richmentorifice connecting said fuel bowl with said conduit posterior tosaid'metering orifice, a valve for controlling said-power enrichmentorifice, a vacuum controlled member for opening said power enrichmentvalve, an accelerating pump yieldably connected to the throttleactuating means, and a means so constructed and arranged as to open saidauxiliary valve for standard engine operation and to close said valve,prevent actuation of the vacuum controlled member of the enrichmentvalve, and limit the stroke of said accelerating pump for split engineoperation.

4. A carburetor for a split engine comprising an induction passage, amain fuel discharge jet for delivering fuel to said induction passage, afuel bowl, a main fuel conduit connecting said discharge jet with saidfuel bowl, a main fuel metering orifice in said conduit, an auxiliaryfuel metering orifice connecting said fuel bowl with said conduitposterior to said main metering orifice, a valve for controlling saidauxiliary orifice, an accelerating pump, and a means so constructed andarranged as to open said auxiliary valvefor standard engine operationand to close said valve and limit the stroke of said accelerating pumpfor split engine operation.

5. A carburetor for a split engineincluding a control means responsiveto variations in at least one engine operating condition of the classconsisting of manifold vacuum, speed, andthrottle position for shiftingthe engine between standard and spit operation, comprising an inductionpassage, a main fuel discharge jet, a fuel bowl, a main-fuel conduitconnecting said discharge jet with said fuel bowl, 2, main meteringorifice in said conduit, an auxiliary fuel metering orifice connectingsaid fuel bowl with said conduit posterior to said main meteringorifice, a valve for controlling said auxiliary orifice, and a meansadapted to be controlled by said control means to open said auxiliaryvalve for standard engine operation and to close said valve for splitengine 7 operation.

6. A carburetor for a split engine comprising an induction passage,

a fuel bowl, a main fuel conduit connecting said induction passage withsaid fuel bowl, a main fuel metering orifice in said conduit, anauxiliary fuel metering orifice -connecting said fuel bowl with saidconduit posterior to said main metering orifice, a valve for controllingsaid auxiliary orifice, and an electrically actuated means soconstructed and arranged as to open said auxiliary valve for standardengine operation, and to close said valve for split engine operation,said electrical means being energized in response to variations in atleast one engine operating condition of the class consisting of manifoldvacuum, speed, temperature and throttle position.

'7. A carburetor for a split engine including a control means responsiveto variations in at least one engine operating condition of the classconsisting of manifold vacuum, speed, and throttle position for shiftingthe engine between standard and split operation, comprising an inductionpassage, a fuel bowl, a main fuel conduit connecting said inductionpassage with said fuel bowl, a main fuel metering orifice in saidconduit, an auxiliary fuel metering orifice connecting said fuel bowlwith said conduit posterior to said main metering orifice, a valve forcontrolling said auxiliary orifice, and a means adapted to be controlledby said control means for regulating said valve to obtain the desiredfuel-air ratio for split engine operation.

8. A carburetor for a split engine comprising an induction passage, afuel bowl, a main fuel conduit connecting said induction passage withsaid fuel bowl, a main fuel metering orifice in said conduit, anauxiliary fuel metering orifice connecting said fuel bowl with saidconduit posterior to said main metering orifice, a valvefor controllingsaid auxiliary orifice, a power enrichment orifice connecting said fuelbowl with said conduit posterior to said main metering orifice, a valvefor controlling said power enrichment orifice, a member for opening saidpower enrichment valve, and means for regulating said auxiliary valveand said member for the power enrichment valve to obtain the desiredfuel-air ratio for split engine operation.

9. A carburetor for a split engine having'a control means for shiftingthe engine between standard and split operation, comprising an inductionpassage, a fuel bowl, a main fuel conduit connecting said inductionpassage with said fuel bowl, a main fuel metering orifice in said con'duit, an auxiliary fuel metering orifice connecting said fuel bowl withsaid conduit posterior to said main metering orifice, a valve forcontrolling said auxiliary orifice, an accelerating pump, and a meansresponsive to the operation of said control means for regulating saidvalve and said accelerating pump to obtain the desired fuel-air ratiofor split engine operation.

10. A carburetor for a. split engine comprising an induction passage, afuel bowl, a main fuel conduit connecting said induction passage withsaid fuel bowl, a main fuel 'metering orifice in said conduit, anauxiliary fuel metering orifice connecting said fuel bowl with saidconduit pos-- terior to said main metering orifice, a valve forcontrolling said auxiliary orifice, a power enrichment orificeconnecting said fuel bowl. with said conduit posterior to said mainmetering orifice, a valve for controlling said power enrichment orifice,a vacuum controlled member for opening said power enrichment valve, anaccel crating pump, and a means for regulating said auxiliary valve,said accelerating pump and said vacuum controlled member for the powerenrichment valve to obtain the desired fuel-air ratio for split engineoperation.

11. A carburetor for a split engine comprising an induction passage, afuel bowl, 2. main fuel conduit connecting said induction passage withsaid fuel bowl, a main fuel metering orifice in said conduit, anauxiliary fuel metering orifice connecting said fuel bowl with saidconduit posterior to said main metering orifice, a valve for controllingsaid auxiliary orifice, a passageway for transmitting manifold vacuum toa spark ad- Vance mechanism, a duct for bleeding air into saidpassageway to lessen the efiect of said vacuum on said mechanism, avalve for controlling said duct, and a means so constructed and arrangedas to open said valves for standard engine operation and to close saidvalves for .split engine operation.

12. A carburetor for a split engine including a control means responsiveto variations in at least one engine operating condition of the classconsisting of. manifold vacuum, speed, and throttle position forshifting the engine between standard and split operation, comprising aninduction passage, a source of fuel, a conduit connecting said sourcewith the induction passage, a metering means in said conduit, a valvularmeans for varying the capacity of said metering means, and means adaptedto be controlled by said control means for regulating said valvularmeans to obtain the desired fuel-air ratio for split engine operation. i

13. A carburetor for a split engine including a control means responsiveto variations in at least one engine operating condition of the classconsisting of manifold vacuum, speed, and throttle position for shiftingthe engine between standard and split operation, comprising an inductionpassage, a source of fuel, a conduit connecting said source with theinduction passage, a metering means in said conduit, a valvular meansfor varying the capacity of said metering means, a power enrichmentmeans connecting said source with the induction passage, a member forcontrolling said power enrichment means, and means adapted to becontrolled by said control means for regulating said valvular meansratio for split engine operation.

15. A carburetor for a split engine having a control means for shiftingthe engine between standard and split operation, comprising an inductionpassage, a fuel bowl, a conduit connecting said fuel bowl with theinduction passage, a metering means in said conduit, a valvular meansfor varying the capacity of said meteringmeans, a power enrichment meansconnecting said fuel bowl with the induction passage, a member forcontrolling said power enrichment means, an accelerating pump, and ameans responsive to the operation of said control means for regulatingsaid valvular means, said member and said accelerating pump to obtainthe desired fuel-air ratio for split engine operation.

ALBERT H. WINKLER.

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